Genetic analysis of reproductive characters of zoysiagrass.

The heredity of reproductive characters,including inflorescence density,reproductive branch height,inflorescence length,specule number of each spike,specule length,specule width and specule length/width ratio,in two F1 populations of Z136×Z039 and Z039×Z136 was analyzed by major gene and polygene mixed genetic models to reveal the genetic mechanism of these characteristics of zoysiagrass.The range of variation of each character in reciprocal progenies was far beyond that of their parents The widest variation was in inflorescence density,followed by the reproductive branch height,specule number of each spike,inflorescence length,specule length,and specule width.Significant differences were observed between two reciprocal crosses for inflorescence density,reproductive branch height,specule length,and specule length/width ratio,which further suggested that there might be maternal genetic phenomenon for these characters in zoysiagrass.There were no significant differences between two reciprocal crosses for inflorescence length,specule number of each spike,and specule width.The inflorescence density from the reciprocal cross Z136 ×Z039 was controlled by a two major gene model.A no major gene model(A-0) was the most suitable model for reproductive branch height,inflorescence length,and specule width of reciprocal crosses,specule number of each spike of negative crosses and the specule length of positive crosses.The specule number of each spike of positive crosses and the specule length of negative crosses of Z136 ×Z039 were controlled by a single major gene model.The most suitable model for the specule length/width ratio of positive crosses was a two additive-dominance-epistasis major genes model(B-1) and the heritability of major genes was 42.72%.A two additive-dominance major genes model(B-2) was the most suitable model for the specule length/width ratio of negative crosses and the heritability of major genes was 98.81%.